Portable Terminal

1. A portable terminal comprising: a main housing; a first sliding housing slidably installed on the main housing in such a manner that the first sliding housing slides in a first direction; two second sliding housings slidably installed on the main housing in such a manner that the two second sliding housings slide in a second direction; a sliding module for providing driving force to move the first and two second sliding housings, the sliding module being installed on the main housing; and guide slots formed on a rear surface of the first sliding housing in such a manner that the guide slots extend along the first direction and guide ribs formed on one surface of a fixed plate, wherein a guide rib is assembled with a guide slot so as to allow the first sliding housing to be assembled with the main housing and to simultaneously guide a sliding of the first sliding housing, wherein the first sliding housing and two second sliding housings simultaneously move from positions where they overlap the main housing to positions where they extend from on the main housing.

2. The portable terminal as claimed in claim 1 , wherein the second direction is perpendicular to the first direction.

3. The portable terminal as claimed in claim 1 , wherein the two second sliding housings move on the main housing in such a manner that they approach or move away from each other, and when they move away from each other, they extend from opposite sides of the main housing.

4. The portable terminal as claimed in claim 1 , wherein the sliding module includes a disc rotatably installed on the main housing, a first link having one end pivotably connected to the disc and another end pivotably connected to the first sliding housing, and two second links each having one end pivotably connected to the disc and another end pivotably connected with one of the two second sliding housings.

5. The portable terminal as claimed in claim 4 , wherein the two second sliding housings are connected with the disc in such a manner that each sliding housing is connected with the disc through one of the second links.

6. The portable terminal as claimed in claim 4 , wherein, as one of the first and second sliding housings slides, the disc is rotated by the first link or one of the two second links connected to the one of the first and second sliding housings, and remaining sliding housings slide according to the rotation of the disc.

7. The portable terminal as claimed in claim 4 , wherein, as the first sliding housing slides, the disc is rotated by the first link connected to the first sliding housing, and the two second sliding housings approach or move away from each other according to the rotation of the disc.

8. The portable terminal as claimed in claim 4 , wherein the sliding module further includes the fixed plate mounted on the main housing, and the disc is rotatably installed on the fixed plate.

9. The portable terminal as claimed in claim 8 , wherein the sliding module includes an elastic member having one end supported by the disc and another end supported by the fixed plate, the elastic member provides an elastic force applied in a direction where both ends of the elastic member move away from each other, and a point where the both ends of the elastic member approach each other to a maximum degree is positioned between a point where the first and two second sliding housings overlap the main housing and a point where they extend from the main housing.

10. The portable terminal as claimed in claim 9 , wherein the elastic member generates a driving force that allows the first and two second sliding housings to move to the point where they overlap the main housing, within an interval between the point where both ends of the elastic member approach each other to a maximum degree and the point where the first and two second sliding housings overlap the main housing, and also generates a driving force that allows the first and two second sliding housings to slide in a direction where they extend from the main housing, within an interval between the point where both ends of the elastic member approach each other to a maximum degree and the point where the first and second sliding housings have been extended from the main housing.

11. The portable terminal as claimed in claim 8 , further comprising a reception recess formed on one surface of the main housing, wherein the reception recess is opened toward both sides of the main housing when the fixed plate is seated on the main housing.

12. The portable terminal as claimed in claim 11 , wherein the two second sliding housings are seated in the reception recess, and the two sliding housings are inserted into or extended from opposite sides of the main housing through a sliding movement on the main housing.

13. The portable terminal as claimed in claim 11 , further comprising guide rails formed on inner walls of upper and lower sides of the reception recess and guide grooves formed on both end walls of the second sliding housings, wherein a guide rail is engaged with a corresponding guide groove so as to allow the second sliding housings to be slidably assembled with the main housing and guide movement of the second sliding housings.

14. The portable terminal as claimed in claim 8 , wherein a part of one surface of the fixed plate is exposed upon the sliding of the first sliding housing, and a first keypad is installed on the exposed part of the fixed plate.

15. The portable terminal as claimed in claim 14 , further including two second keypads, one installed on each of the two second sliding housings, wherein, when the first and second sliding housings are extended from opposite sides of the main housing, a keypad having qwerty keypad arrangement is formed by the first keypad and the second keypads.